Targeted and Untargeted Metabolomics to Explore the Bioavailability of the Secoiridoids from a Seed/Fruit Extract (Fraxinus angustifolia Vahl) in Human Healthy Volunteers: A Preliminary Study

Abstract

Abstract:The bark, seeds, fruits and leaves of the genus Fraxinus (Oleaceae) which contain a wide range of phytochemicals, mostly secoiridoid glucosides, have been widely used in folk medicine against a number of ailments, yet little is known about the metabolism and uptake of the major Fraxinus components. The aim of this work was to advance in the knowledge on the bioavailability of the secoiridoids present in a Fraxinus angustifolia Vahl seed/fruit extract using both targeted and untargeted metabolomic analyses. Plasma and urine samples from nine healthy volunteers were taken at specific time intervals following the intake of the extract and analyzed by UPLC-ESI-QTOF. Predicted metabolites such as tyrosol and ligstroside-aglycone glucuronides and sulfates were detected at low intensity. These compounds reached peak plasma levels 2 h after the intake and exhibited high variability among the participants. The ligstroside-aglycone conjugates may be considered as potential biomarkers of the Fraxinus secoiridoids intake. Using the untargeted approach we additionally detected phenolic conjugates identified as ferulic acid and caffeic acid sulfates, as well as hydroxybenzyl and hydroxyphenylacetaldehyde sulfate derivatives which support further metabolism of the secoiridoids by phase I and (or) microbial enzymes. Overall, the results of this study suggest low uptake of intact secoiridoids from a Fraxinus angustifolia Vahl extract in healthy human volunteers and metabolic conversion by esterases, glycosidases, and phase II sulfo-and glucuronosyl transferases to form smaller conjugated derivatives.

Application of UHPLC-ESI-Q-TOF-MS to Identify Multiple Constituents in Processed Products of the Herbal Medicine Ligustri Lucidi Fructus

“…The Extracted Ion Chromatogram (EIC) at m / z 1071.3562 displayed four peaks ( 31 , 35 , 37 , 38 ) with almost the same fragmentation profiles ( m / z 909, 839, 685, 523, 453, 403, 385) characteristic for G13 and its isomers [ 13 , 30 ], which were possibly nuezhenide with an additional oleoside 11-methyl ester moiety. The fragments at m / z 685 and 403 could be assigned to the deprotonated ions of nuezhenide and oleoside 11-methyl ester, respectively.…”

E4An Ultrastructural Study by Transmission Electron Microscope of Exocrine Pancreatic Cells in Diabetic Rats Treated with Herbal Combination

“…The seeds, bark, leaves, and fruits of the genus Fraxinus have been greatly consumed in folk medicine against a multiple of diseases. The genus Fraxinus includes a broad group of phytochemicals, mainly secoiridoid glucosides (22). An extract of Fraxinus fruits/seeds has been exhibited to cause a significant decrease in glycemia, triglyceridemia in addition to pressure of blood in several animal models of obesity, hypertension, and diabetes (23).…”

Simultaneous untargeted and targeted metabolomics profiling of underivatized primary metabolites in sulfur-deficient barley by ultra-high performance liquid chromatography-quadrupole/time-of-flight mass spectrometry

“…It is worth to mention that simultaneous targeted and untargeted metabolomics was applied in a phytomedicine study [ 36 ]. However, none of the reported studies showed this approach on the study of primary metabolites in plant metabolomics.…”